Dwight, I had weird problems with the 84 Westy temp gauge as follows.  The
light came on and flashed mostly continuously but the engine temp was OK.
>From the net I was advised to check the mix of water and coolant - should
be 50/50!  I was doig this over about a month when the temp needle started
to only come up about 1 needle width.  Then the fuel gauge started to
register only about 1/4 full when it was full!

Finally replaced the "voltage stabilizer" in the dash panel ($15) and all
was well.  Hope this helps.
Don.